usb: dwc3: Add a check for the DWC_usb3 core

Add a helper function to check if we are running on a DWC_usb3 core.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index b9903c6..354de24 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -1148,6 +1148,12 @@
 void dwc3_set_mode(struct dwc3 *dwc, u32 mode);
 u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type);
 
+/* check whether we are on the DWC_usb3 core */
+static inline bool dwc3_is_usb3(struct dwc3 *dwc)
+{
+	return !(dwc->revision & DWC3_REVISION_IS_DWC31);
+}
+
 /* check whether we are on the DWC_usb31 core */
 static inline bool dwc3_is_usb31(struct dwc3 *dwc)
 {